Note places that have become milky white (10)

I believe the answer is:

opalescent

I'm a little stuck... Click here to teach me more about this clue!

'milky white' is the definition.
(I've seen this in another clue)

'note places that have' is the wordplay.
'note places' can be anagrammed to 'OPALESCENT'.
Though, I'm unsure how this is indicated.

'become' is the link.

Can you help me to learn more?

(Other definitions for opalescent that I've seen before include "Shot" , "Sparkling" , "shimmering" .)

I've seen this clue in The Irish Independent.

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